/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 1999-2002 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Xerces" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 1999, International
 * Business Machines, Inc., http://www.apache.org.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package com.sun.org.apache.xerces.internal.impl.dtd.models;

import com.sun.org.apache.xerces.internal.impl.dtd.XMLContentSpec;

/**
 * Content model Bin-Op node.
 *
 * @xerces.internal
 */
public class CMBinOp extends CMNode {

  // -------------------------------------------------------------------
  //  Constructors
  // -------------------------------------------------------------------
  public CMBinOp(int type, CMNode leftNode, CMNode rightNode) {
    super(type);

    // Insure that its one of the types we require
    if ((type() != XMLContentSpec.CONTENTSPECNODE_CHOICE)
        && (type() != XMLContentSpec.CONTENTSPECNODE_SEQ)) {
      throw new RuntimeException("ImplementationMessages.VAL_BST");
    }

    // Store the nodes and init any data that needs it
    fLeftChild = leftNode;
    fRightChild = rightNode;
  }


  // -------------------------------------------------------------------
  //  Package, final methods
  // -------------------------------------------------------------------
  final CMNode getLeft() {
    return fLeftChild;
  }

  final CMNode getRight() {
    return fRightChild;
  }


  // -------------------------------------------------------------------
  //  Package, inherited methods
  // -------------------------------------------------------------------
  public boolean isNullable() {
    //
    //  If its an alternation, then if either child is nullable then
    //  this node is nullable. If its a concatenation, then both of
    //  them have to be nullable.
    //
    if (type() == XMLContentSpec.CONTENTSPECNODE_CHOICE) {
      return (fLeftChild.isNullable() || fRightChild.isNullable());
    } else if (type() == XMLContentSpec.CONTENTSPECNODE_SEQ) {
      return (fLeftChild.isNullable() && fRightChild.isNullable());
    } else {
      throw new RuntimeException("ImplementationMessages.VAL_BST");
    }
  }


  // -------------------------------------------------------------------
  //  Protected, inherited methods
  // -------------------------------------------------------------------
  protected void calcFirstPos(CMStateSet toSet) {
    if (type() == XMLContentSpec.CONTENTSPECNODE_CHOICE) {
      // Its the the union of the first positions of our children.
      toSet.setTo(fLeftChild.firstPos());
      toSet.union(fRightChild.firstPos());
    } else if (type() == XMLContentSpec.CONTENTSPECNODE_SEQ) {
      //
      //  If our left child is nullable, then its the union of our
      //  children's first positions. Else is our left child's first
      //  positions.
      //
      toSet.setTo(fLeftChild.firstPos());
      if (fLeftChild.isNullable()) {
        toSet.union(fRightChild.firstPos());
      }
    } else {
      throw new RuntimeException("ImplementationMessages.VAL_BST");
    }
  }

  protected void calcLastPos(CMStateSet toSet) {
    if (type() == XMLContentSpec.CONTENTSPECNODE_CHOICE) {
      // Its the the union of the first positions of our children.
      toSet.setTo(fLeftChild.lastPos());
      toSet.union(fRightChild.lastPos());
    } else if (type() == XMLContentSpec.CONTENTSPECNODE_SEQ) {
      //
      //  If our right child is nullable, then its the union of our
      //  children's last positions. Else is our right child's last
      //  positions.
      //
      toSet.setTo(fRightChild.lastPos());
      if (fRightChild.isNullable()) {
        toSet.union(fLeftChild.lastPos());
      }
    } else {
      throw new RuntimeException("ImplementationMessages.VAL_BST");
    }
  }


  // -------------------------------------------------------------------
  //  Private data members
  //
  //  fLeftChild
  //  fRightChild
  //      These are the references to the two nodes that are on either
  //      side of this binary operation.
  // -------------------------------------------------------------------
  private CMNode fLeftChild;
  private CMNode fRightChild;
};
